audk/MdePkg/Library/BaseLib/Ia32/LShiftU64.asm

47 lines
1.4 KiB
NASM

;------------------------------------------------------------------------------
;
; Copyright (c) 2006, Intel Corporation
; All rights reserved. This program and the accompanying materials
; are licensed and made available under the terms and conditions of the BSD License
; which accompanies this distribution. The full text of the license may be found at
; http://opensource.org/licenses/bsd-license.php
;
; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
;
; Module Name:
;
; LShiftU64.asm
;
; Abstract:
;
; 64-bit left shift function for IA-32
;
;------------------------------------------------------------------------------
.686
.model flat,C
.code
;------------------------------------------------------------------------------
; UINT64
; EFIAPI
; InternalMathLShiftU64 (
; IN UINT64 Operand,
; IN UINTN Count
; );
;------------------------------------------------------------------------------
InternalMathLShiftU64 PROC
mov cl, [esp + 12]
xor eax, eax
mov edx, [esp + 4]
test cl, 32 ; Count >= 32?
cmovz eax, edx
cmovz edx, [esp + 8]
shld edx, eax, cl
shl eax, cl
ret
InternalMathLShiftU64 ENDP
END